Controlling mechanism



Nov. 20, 1928.

1,692,266 F. D. HoLDswoR-rl-l I CONTROLLING MECHANISM Filed Sept. 15, 19,25

Mw ,N l m.

M l (7W Patented Nov. 2o, 192s.

UNITED AS'I'MEsparENT oFFicE.

FRED D. HOLDSWORTH, F CLABEMONT, NEW HAMPSHIRE, ASSIGNOR '.l SULLIVAN v MACHINERY COMPANY, A CORPCRATION OF MASSACHUSETTS.

' .coNTnoLLING 4izrnc'inalvsnacr.

' Application iled September 15, 1925.' Serial No. 56,538.

While this invention relates generally to im rovements in controlling mechanisms, it

Howto a compressor driving mechanism and to eect load control of the compressor.

In compressor mechanisms itis usual to have means for controlling the compressor load in accordance with receiver pressure and when the compressor is unloaded it is desirable to reduce power Howto the compressor driving mechanism. While this driving mechanism herein specifically takes the form of an internal combustion engine, power flow thereto being controlled by a valve in the intake manifold, yet it will be clear that broadly the driving mechanism could be of any other t pe such as an electric motor and that power ow thereto l would be controlled by any usual mechanism associated with that type of motor. When reloading of the compressor occurs it is desirable that power flow to the motor should have been increased'a'sufcient time before the compressor is reloaded to enable the motor to have developed suflicient power to ca rry the full load that is ordinarily suddenly thrust upon the compressor due to quick reloading thereof.

It is accordingl an object of my invention to reduce power gow to the; motor when the compressoris ,unloaded and further to inA crease power iow to the motor just prior to` loading of the compressor. In one specificvas ectl of the invention I accomplish these obJects by controlling the intake manifold valve AY'on an internal combustion engine by a pneumatically actuated mechanism which also controls fluid flow to a usual type of compressor load controlling' mechanism. rlfhe parts are so arranged that prior to loading vof the compressor the engine throttle valve will be opened first, thereby increasing the power developed.

A 'further object is to provide improved means whereby the engine throttle valve can be controlled independently ,of compressor unloading, which means, in one specific aspect of the invention, includes means for limiting the closing limit of the throttle valve, thereby permitting predetermined power flow tothe krunning idle.

In the accompanying drawings I have shown for purposes of illustration two forms which my lnvention may assume in practice.

In/these drawings,- Fig. 1 is a side elevationof a portable compressor embodying my invention.

motor while the same is Fig. 2 is a vertical section through the copendig application, Serial No. 706,583, i

filed Apr. 14, 1924, and identical thereto in such respects as the type of compressor unloading mechanism and the general arrange- 'ment of parts. Briefly, this outfit comprises a motor 1 preferably of the internal combustion engine type which is adapted. through suitable connections to-actuate a compressor `2 carrying unloading mechanisms 3 and 4. The unloading mechanism is actuated by pressure fluid yfiowing from a receiver 5 through pipes 6, 7, 8, 9 and 10 and branch pipes-11 and 12. 'An unloader pilot valve 13 has communication with the pipes 6 and 7 to permitflow of fluid into the pipe 7 ywhen a predetermined high pressure is had in the receiver v5 .and t0 exhaust the pressure fluid in value is reached.

To control power flow to the motor and. to actuate the unloading mechanism a controlling mechanism 15 hasV communication with the pipes 8 and 9. This controlling mechanism comprises a casing 19 having a 4 cylinder bore 20 within which a piston 21 is reciprocably'mounted. A head 22 secured to the cylinder has an opening to receive the pipe 8 which terminates adjacent an annular valve seat forming flange 24. A spring 25 is interposed between the top of the piston andan upper cylinder head 26. The piston has a stop portion28 engageable with a downthe pipes 7 and 8 when a predetermined lowv wardly projecting portion 29 of the head 26, while a stem 30. extends upwardly through a bore in the head. Adjustably threadedly mounted upon the stem is a tappet` block 31 for engaging one arm 32A of a bell crank whichis pivotally mounted as at 33 upon an arm 34 extending [upwardly from and carried by the cylinder head 26. The other arm 35 of the bellcrank has a series of holes 36 therein to receive adjustably one end of a rod 37 which at its other end is connected to a butterfly valve 16 disposed in the intake manifold of the engine. A spring 38 normally tends to keep thearm 32 in contact with the member 31, but it will be clear that if for any reason the operator desires .to increase power flow to the engine he may move the bell crank to actuate the butterfly valve without affecting the controlling mechanism.

When the receiver pressure reaches a predetermined high value, the pilot valve 13 will permit fluid to flow through the pipes 7 and 8,`thereby forcing the piston 21 Ifrom its seat 24 to move the butteriiy Valve towards its closing position. Fluid for actuating the unloadino' mechanisms 3 and 4 is controlled by the piston 21 which opens a passage 40 formed in a projecting boss 41 carried by the cylinder 19. A passage 42 leading to the pipe 9 and to an exhaust port 43 is adapted to have communication with the passage byway of'a passage 44 which is controlled by a valve 45. Access to the valve 45 is had ,85' through an opening normally' closedv by a removable plug 46. y

In operation, assuming that receiver pressure has reached its predetermined high value,

fluid will flow past-the unloading valve 13vrr and raise the piston 21 to move the intake valve to closing position and also uncover and cover respectively.` the 'passages 40 and 42. When the passage 40 is uncovered, which cannot happen until after the passage 42 has been covered, due to the length of the piston 21, fluid pressure will raise the valve 45 'allowing fluid to flow to the unloading mechanisms 3 and 4. When receiver pressure has fallen to a predetermined low value, the pipe 8*-w-illbe vented to the atmosphere by the pilot valve mechanism 13, thereby allowing the spring 25 to force the piston 21 downwardly upon the seat 24 and thereby permitting the spring 38 to move the intake valve to open position. It will be noted however that the piston 21 travels downwardly a predeterminedv distance before the passage 42 has Comunication with the atmosphere as by way of the cylinder 20 and exhaust port 43. Hencethe engine throttle valve will be opened prior to the release of the unloading mechanism actuating, pressure, thereby giving the engine a chance to increase its speed before the compressor is loaded. While the piston 21 is descending and the passages 42 and 40 are closed and opened respectively, the valve 45 this time the enginewill have developed suficientpower for carrying the load.

In Figs. 4 and 5 I have shown a modified form. of my invention which differs from the preferred form in the genera-l arrangement of arts and in having the further feature of being able to control the closing limit of the engine, throttle `valve independently of the controlling mechanism', although it will be clear that this limiting means is readily' adaptable to the preferred form. This controlling mechansm comprises a cylinder having a flanged annular machinedportion 51 '.hich is slidably received ina bore 52 of the housing 53. A member 54 forming a cylinder head has a recess 54n which receivesk an annular portion of the housing -53. The cylinder 50, housing 53, and member 54 may be.

secured together in any desired manner such as by forced fits or the like. A two-spool piston 55 carries a valve portion 5 6 and a stem 57 which adj ustably carries a tappet 58. A spring 59 is disposed between the piston and a cylinder head 60 which carries an arm 61. A bell crank including an arm 62 to which is attached the engine throttle valve rod 37 is pivotally mounted'upon the arm 61 as at 63 while the other arm 64 of the bell crank engages the tappet 58. The valve 56 controls va passage 65 which has communication with a passage 66 and pipe 8, the latter leading from the pilot valve 13. Flow of fluid to the unloading mechanism is permitted after `the' piston 55 has moved a predetermined discommunicate respectively with passages 74 and 75. Communication between these passages as by a passage 76 -is controlled by a valve 77 disposedin the passage 74. This valve may be removed as throughan opening normally closed by a removable plug 78. The pipe 9 which leads to the unloading mechanism is in communication with the annular groove 71 and is adapted to be placed in communication through it and the interior of the cylinder 50 with an exhaust port 7 9 leading from the cylinder 50.

To control variably the closing limit of the engine throttle valve a lever 480 pivotally mounted upon the pivot. 63 carries apin 81 engageable with the arm 62. An arm 82 lixed to the lever 80'is adapted to be held as by a wing nut 83 cooperating with a slotted memto limit rearward movement ofthe arm 62 1-,692,266 i A I ber A84 which pim-)tallyv mounted on the cylinder 50 as ati 85. The nut 83-when loosened may be moved downwardl or upwardly within the slotted portion of t e member` 84 and clamped in any desired position, thereby b engagement thereof with the pin 81. spring 86 normally tends to keep either -the arm 62 in contact with the pin 81 or the arm 64 in contact with the tappet 58.

Operation of this form of the device is substantially the same as the preferred form in thatwhen receiver ressure reaches a predetermined amount t e piston 55 will be moved to close the engine throttle valve and to allow fiow of fiuid past the valve 77 through the passages 76, r75 and annular -groovefl tothe pipe 9. It will be seen,

owever, thatl the radial ports 78 will be closed prior to the'opening ofthe ports72.

v- Reverse movement of the iston 55 is effected by the spring 59 when, ue to tlie'receiver pressure reaching its predetermined low.

. to carry the full load. As soon as the pressure in the pipe 8 and .passage 66 falls, due to being vented to the atmosphere by the pilot valve 13,'the valve 77 willbe closed bythe s pressure in the pipe 9,l thereby maintaining the compressor unloaded until the piston un-/predetelmllled mOVement 0f Sad Plstondisposed in a horizontal might be had.

covers the ports 73 to vent the unloading actuating pressure' Huid, to the atmosphere 'through the exhaust port 79. The modified form of the device has the piston preferably lposition although it will be clear` that any ot er position thereof By having an interval of time between opening of the engine throttle valve and loading of the compressor, undue vibration is prevented for it has been found tha.t.t vitl1 out this time relation th engine will vibrate considerably duel to it being necessaryto bring a full load at'a relatively low speed up to a normal runningspeed. lso by having a reduced piston area such as caused by the annular valve seating surface 24 and the reduced valve 56 exposed to the pressure in the line 8 the respective piston will not be moved until substantially full receiver pressure has beenv created in the line 8. When the pistons Vhave very slightly vmoved off their seats, fluid williiowfto the entire piston area which will create an actuating force far greater than is necessary to move the piston. Accordingly, the4 pistons will move rapidly .past the controlled passages, thereby eliminating any sluggish action of the controlled elements.

While I have in this application specifically described two forms which my invention may/'assume in practice, it is to be understood that these forms of the same'are shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.'

What I claim as new and desire to secure by I LettersPa-tent is:

1. A controlling mechanism comprising a controlled element', a cylinder, afluid responsive piston therein adaptedto have operative connection with said element, a conduit for leading pressure fiuid to said cylinder,`a second conduit leading from said cylinder, the .said piston being movable in said c linder so that in one position the flow of uid 'to said second conduit is obstructed by said piston and in another position the .flow is permitted, and means for maintaining fluid pressure in said second conduit-.duringrelease of the actuating fluid pressure for said piston.

1 2. A controlling mechamsm comprising a controlledelement, a cylinder, a fluid responsive l piston therein mechanically connected with' said element, a conduit for leading pressure fluid -to said cylinder, a second conduit leading from said cylinder. the said piston being movable in said cylinder so that in one position the fiow of fiuid to said second conduit is obstructed by said piston and in another position the flow is permitted, and means for venting said'secondconduit upon 3. A controlling mechanism-comprising a cylinder with a piston therein, means providing main and auxiliary passages both communicating with said cylinder, said piston being movable in said cylinder so as to permit fluid to fiow fromsaid cylinder to said main passage through said auxiliary passage, and means whereby flowfof fiuidy from said main passage to said auxiliary passage is prevented when pressure ofthe iuid in said auxiliary passage isreduced.

4. The combination with a. compressor, a driving motor therefor, and a receiver, of

uid'pressure operated unloading means for said compressor, a control for said motor, a conduit for supplying pressure fluid from the receiver to the unloading means to actuate the same, and a valve mea-ns in said conduit comprising 'an element adaptedto be displaced by. the passage of pressure fluid to the unloading means, said element being mechanically connected to said motor control so as to shift said motor control when pressure fluid is supplied to'the unloading means vfor the comprcssor.'- f

" 5. The combination with a compressor and lao cylinder, a pair of passages communicating a driving motor therefor, of fluid pressure operated unloading means for said compressor, a control'for said motor, a conduit for leading fluid compressed by said compressor to said unloading means, a valve means in said conduit comprising an element adapted to be displaced by the passage of pressure with saidcylinder, a passage connecting said other passages, a check valve for lpermitting flow in one direction through said connecting passage but preventing flow in the opposite direction, and a piston movable in said cylinder to control said pair of passages.

7. A controlling mechanism comprising a cylinder, a pair of passages communicating with said cylinder, a passage connecting said 4 other passages, a check valve for permitting flow in one 4direction through said connecting passage but preventing llow in the opposite direction, a piston movable in said cylinder to control said pair of passages, the entrances to said pair of passages from said cylinder being longitudinally spaced along the said cylinder. f

8. The combination with a compressor and a driving motor therefor, of unloading means for said compressor, movable means adapted when in one position to obstruct operation of the unloading means and in another position to permit operation of thennloading means, a control for the flow of motive medium to said motor mechanically connected to said movable means so that movement of the latter to permit operation of the unloading means shifts said control in one direction and movement to obstruct operation of the unloading means shifts said control in the opposite direction.

9. The combination with a compressor and 'a driving motor therefor, of unloading means for said compressor, movable means adapted vwhen in one position to obstruct operation of the unloading means and in another position to permit operation` of the unloading means, a control for the ilow of motive medium to said motor having a link connection to said movable means so that movement of the latter' to permit operation of the unloadingmeans shifts said control in one direction and movement to obstruct operation of .the unloading means shifts said control in the opposite direction. v

10. The combination with fa compressor and a driving motor therefor, of unloading means for said compressor includingm'eans for conducting actuating medium to said unloading means, a movable member a portion of which is disposed in said conducting means when in one position so as to obstruct flow of actuating medium to said unloading means and when in another position permits flow ofactuating medium to said unloading means, and a control for said motor mechanically connected to said movable member so that movement of the latter to permit operation of the unloading' means shifts said control in one direction andv movement to obstruct operation 'of the unloading means shifts said control in the opposite direction.

11. The combination with a compressor and a driving motor therefor, of unloading means for said compressor, means forming a lyielding obstruction t0 the operation of the said unloading means, and a control for said motor mechamcallv connected to `said yielding means so thatthe yielding of the latter to permit operation of the unloading means shifts said control.

12. The combination with a. compressor, a .driving motor therefor and a receiver, of fluid pressure operated unloading means -for'said compressor, a conduit for supplying pressure fluid from the receiver to the unloading means to actuate .the same, means intermediate the ends of the conduit forming a yieldable obstruction to the flow of such lluid to the unloading means,.and a cont-rol for said motor mechanically connected to 'said yielding means so that the yielding of the latter to permit'flow of actuating lluid to the unloading means shifts said motor control.

13.\The combination with a compressor, a driving motor therefor, and a receiver, of fluid pressure operated unloading means for said compressor, a conduit for supplying pressure fluid from the receiver to the unloading means to actuate the same, a member necessarily movable to permitlow of fluid through said conduit, and a motor controlling element mechanically connected to said movable member so that movement of the latter topermit flow of fluid to the unloading means shifts saidcontrolling element.

14. A controlling mechanism comprising a cylinder having a piston therein, means forming a pair of passages communicating with said cylinder, a by-pass connecting said passages, means permitting lluid flow in one-direction through said by-pass but preventing flow in the opposite direction, and vent means' v means.

15. The combination with a compressor provided with a driving motor, of controlling mechanism therefor comprising controlling means for said motor, pressure fluid lll actuated unloading means for said compressor, aconduit for leading pressure fluid to' said unloading means,lcontrolling mechanism interposed in said conduit comprising a movable element havinga surface subject to fluid pressure, said controlling mechanism having a fluid supply port controlled by movement of said element so that in one position the flow of fluid to said unloading 10 means is obstructed and in another position the flow is permitted, and a vent port also controlled by movement of said element so as to vent upon predetermined movementof said element'the Huid previously supplied to said unloading means, said element being mechan- 15 ically connected to said motor contr lling means.

In testimony whereof I aix my signature.

l FRED D. HOLDSWORTH. 

